Dear Sara, what you do is correct, the BH molecule is the molecule in the chemical equation, whereas, the insertion of one H atom (BH2+ molecule) is the (moleculeH)+. However, I have a doubt, do you used the BH acid like an example? I ask to you because the B is localized in the group 13 of periodic table, then, the acid formed would be the BH3. If you simulated the BH molecule like example or to learn about proton affinity there is not problem.